This invention relates generally to hydraulic systems and more particularly to a new and novel improved quick release system for tightening and releasing tug and barge cable connections during the normal operation of the tug and also during emergency conditions.
In the operation of a tug utilized in handling a single barge unit, the tug is generally positioned in a notch in the stern of the barge unit with two cables, one of each side, connecting the stern of the tug to the barge unit. It is highly desirable to be able to tighten these cables periodically as the barge is being towed and also in the event of an emergency or upon normal release conditions to be able to quickly release the cables from the tug.
Prior art hydraulic systems for releasing the cables from the barges generally included the use of electric operated spool valves connected in common to a pair of hydraulic pumps which actuated the respective cylinders one at a time and in a very slow manner. Such prior art systems, while satisfactory for some conditions, were not generally satisfactory for emergency conditions wherein it is highly desirable to be able to quickly release one cable from the tug in the event that the opposite cable breaks. This condition can be very dangerous to the tug operator and the other persons on the tug boat because if the break occurs whenever the tug is pushing the single barge, the barge will actually pull the tug and possibly turn it over or make it list at a dangerous angle in the water.
Such prior art systems also generally had no fail-safe feature in that, if the generator on the tug developed troubles and went out of commission, no auxiliary system was provided to enable the cables to be released from the barge during normal operations or in an emergency. In order to release the cables under these conditions, the deck hands would have to proceed to the back deck of the tug and handle various manual valves in order to manually release the cables, requiring them to work at times in water up to their waist in order to get the tug loose from the barge.